This bear trap is pressure sensitive and doesn't require any special procedure or trigger to make it work, you just push the orange connectors down with either your fingers or your foot. One major flaw would be that if you put the wrong kind of bands on the teeth will either go underneath or won't set properly.
V1.0 Basic trap with rubber bands in the way of the foot.
V1.3 Put the rubber bands under the main grey rod to stop it from getting in the way.
V1.5 Changed the teeth so that they interlock.
V1.9 Changed the grey rods to red rods to make it more compact.
Step 1: Making the Side Rings and Frame
Does what it says in the title.
Step 2: The Centre Piece
You really don't need a description.
Step 3: Teeth and Connection
Step 4: Rubberband and Usage
This is where it becomes annoying with the flaw.
To use the trap:
1) Place on ground
2) Pull teeth apart and pull them back until they don't shut. ie. when the band is around horizontal.
3) Wait for very stupid creature to walk into it.
When the orange connectors are pushed down, the teeth spring up and shut.